DEFSTAN 02-381/1(2009) : 2009

Foreword
1 Scope
2 Warning
3 Normative References
4 Definitions
5 Abbreviations
6 Manufacturer's Qualification Approval
7 Manufacture
  7.1 Carburised and Hardened Gears
      7.1.1 At the Steelmaker's Works
            7.1.1.1 Steelmaking
            7.1.1.2 Ingots and Blooms
            7.1.1.3 Minimum Discards
            7.1.1.4 Test Pieces
      7.1.2 At the Forgemaster's Works
            7.1.2.1 Hot Working
            7.1.2.2 Provision of Test Pieces
            7.1.2.3 Refining Normalising
            7.1.2.4 Stress Relieving
            7.1.2.5 Machining and Prolongation Sectioning
      7.1.3 At the Gear Manufacturer's Works
            7.1.3.1 Machining the Teeth
            7.1.3.2 Heat Treatment
            7.1.3.3 Shot Peening, Cleaning and Blasting
            7.1.3.4 Cutting-off the Prolongation
            7.1.3.5 Finishing
  7.2 Nitrided Gears
      7.2.1 At the Steelmakers Works
            7.2.1.1 Steelmaking
            7.2.1.2 Ingots and Blooms
            7.2.1.3 Minimum Discards
            7.2.1.4 Test Pieces
      7.2.2 At the Forgemaster's Works
            7.2.2.1 Hot Working
            7.2.2.2 Provision of Test Pieces
            7.2.2.3 Refining Normalising
            7.2.2.4 Stress Relieving
            7.2.2.5 Initial Machining
            7.2.2.6 Hardening and Tempering
            7.2.2.7 Machining and Cutting Off the Prolongation
      7.2.3 At the Gear Manufacturer's Works
            7.2.3.1 Machining the Teeth
            7.2.3.2 Stress Relieving
            7.2.3.3 Nitriding
            7.2.3.4 Finishing
  7.3 Induction Hardened Gears
      7.3.1 At the Steelmakers Works
            7.3.1.1 Steelmaking
            7.3.1.2 Ingots and Blooms
            7.3.1.3 Minimum Discards
            7.3.1.4 Test Pieces
      7.3.2 At the Forgemaster's Works
            7.3.2.1 Hot Working
            7.3.2.2 Provision of Test Pieces
            7.3.2.3 Refining Normalising
            7.3.2.4 Stress Relieving
            7.3.2.5 Initial Machining
            7.3.2.6 Hardening and Tempering
            7.3.2.7 Machining and Cutting Off the Prolongation
      7.3.3 At the Gear Manufacturer's Works
            7.3.3.1 Heat Treatment
            7.3.3.2 Induction Hardening Trials on the Test Arcs
            7.3.3.3 Induction Hardening
            7.3.3.4 Tempering
            7.3.3.5 Shot Peening, Cleaning or Blasting
            7.3.3.6 Finishing
8 Testing, Inspection and Acceptance Standards
  8.1 Carburised and Hardened Gears
      8.1.1 At the Steelmaker's Works
            8.1.1.1 Ladle Analysis - Carburised and Hardened
                     Gears
            8.1.1.2 Steel Cleanness
      8.1.2 At the Forgemaster's Works
            8.1.2.1 Jominy Test
            8.1.2.2 Product Analysis
            8.1.2.3 Grain Size
            8.1.2.4 Tensile and Charpy Tests
            8.1.2.5 Hardness Test on the Forging
            8.1.2.6 Non-Destructive Examination of the Forging
      8.1.3 At the Gear Manufacturer's Works
            8.1.3.1 Provision of Test Pieces
            8.1.3.2 Tensile and Charpy Tests
            8.1.3.3 Case Depth
            8.1.3.4 Percentage Retained Austenite
            8.1.3.5 Carbide Precipitation Level
            8.1.3.6 Intergranular Oxidation
            8.1.3.7 Hardness Tests on Tooth Flanks
            8.1.3.8 Non-Destructive Examination of the Gear
            8.1.3.9 Grinding Burns
            8.1.3.10 Non Conformity
  8.2 Nitrided Gears
      8.2.1 At the Steelmaker's Works
            8.2.1.1 Ladle Analysis - Nitrided Gears
            8.2.1.2 Steel Cleanness
      8.2.2 At the Forgemaster's Works
            8.2.2.1 Product Analysis
            8.2.2.2 Grain Size
            8.2.2.3 Tensile and Charpy Tests
            8.2.2.4 Hardness Test of the Forging
            8.2.2.5 Non-Destructive Examination of the Forging
      8.2.3 At the Gear Manufacturer's Works
            8.2.3.1 Provision of Test Pieces
            8.2.3.2 Case Depth
            8.2.3.3 Hardness Tests of Tooth Flanks
            8.2.3.4 Non-Destructive Examination of the Gear
            8.2.3.5 Non Conformity
  8.3 Induction Hardened Gears
      8.3.1 At the Steelmaker's Works
            8.3.1.1 Ladle Analysis
            8.3.1.2 Steel Cleanness
      8.3.2 At the Forgemaster's Works
            8.3.2.1 Product Analysis
            8.3.2.2 Grain Size
            8.3.2.3 Tensile and Charpy Tests
            8.3.2.4 Hardness Test on the Forging
            8.3.2.5 Non-Destructive Examination of the Forging
      8.3.3 At the Gear Manufacturer's Works
            8.3.3.1 Examination of the Induction Hardening
                     Trial Test Arcs
            8.3.3.2 Visual Examination of the Gear Teeth
            8.3.3.3 Etching the Gear Teeth
            8.3.3.4 Hardness Tests on Tooth Flanks
            8.3.3.5 Non-Destructive Examination of the Gear
            8.3.3.6 Grinding Burns
            8.3.3.7 Non Conformity
9 Quality Assurance, Identification and Documentation
  9.1 Quality Assurance
  9.2 Identification
  9.3 Documentation and Certification
Annex A - Normative References
Annex B - Magnetic Particle Examination (MPE) of Gears
  B.1 General
  B.2 Magnetising Techniques
      B.2.1 Pinion Forgings
      B.2.2 Wheel Forgings
      B.2.3 Pinion Teeth
      B.2.4 Wheel Teeth
      B.2.5 Magnetic Flaw Detection Medium
  B.3 Inspection
  B.4 Interpretation
  B.5 Recording Indications
  B.6 Demagnetisation
Annex C - Ultrasonic Examination (UE) of Forgings and Gear Teeth
  C.1 General
  C.2 Surface Preparations
  C.3 Techniques - Forgings
  C.4 Wheel and Rim Forgings
  C.5 Pinion Forgings
  C.6 Tooth Examination

Specifies the requirements for the manufacture, heat treatment, testing and inspection related to the three processes used in the forging and heat treatment of main propulsion gears for use in Naval vessels: 1) Carburised and hardened; 2) Nitrided; 3) Induction hardened.